Question

我已经在SQL Server中计算了地理距离过程，但是它具有别名列，并且无法将排序属性设置为true；

DECLARE
    @GEO1 GEOGRAPHY,
    @LAT VARCHAR(10),
    @LONG VARCHAR(10)

SET @LAT = '41.000000'
SET @LONG = '30.000000'

SET @geo1 = geography::Point(@LAT, @LONG, 4326)

SELECT 
    LOC_ID, LOC_NAME,
    LEFT(CONVERT(VARCHAR, (@geo1.STDistance(geography::Point(ISNULL(LAT,0), ISNULL(LONG, 0), 4326))) / 1000), 4) AS DISTANCE
FROM
    Konum
WHERE 
   (@geo1.STDistance(geography::Point(ISNULL(LAT,0), ISNULL(LONG,0), 4326))) / 1000 < 10

我尝试了

DECLARE
    @GEO1 GEOGRAPHY,
    @LAT VARCHAR(10),
    @LONG VARCHAR(10)

SET @LAT = '41.329867'
SET @LONG = '36.264149'

SET @geo1= geography::Point(@LAT, @LONG, 4326)

SELECT 
    LOC_ID, LOC_NAME,
    LEFT(CONVERT(VARCHAR, (@geo1.STDistance(geography::Point(ISNULL(LAT, 0), ISNULL(LONG, 0), 4326))) / 1000), 4) AS DISTANCE
FROM
    Konum
WHERE 
    (@geo1.STDistance(geography::Point(ISNULL(LAT, 0), ISNULL(LONG, 0), 4326))) / 1000 < 30
ORDER BY 
    DISTANCE ASC -- <=

但是返回别名varchar列

1.2
1.3
11.5 <= Not like
2.8
9.7

我尝试过：

CAST(DISTANCE AS INT)

但是SMSS抛出错误“无效的列名'DISTANCE'”，因为它是列别名。

如何解决此问题？

Answer 1

您的距离列当前是一个字符串，因此将按此排序。删除字符串转换（LEFT(CONVERT(VARCHAR），它将正确排序。

DECLARE @GEO1 GEOGRAPHY, @LAT VARCHAR(10) = '41.329867', @LONG VARCHAR(10) = '36.264149'

SET @geo1= geography::Point(@LAT, @LONG, 4326)

SELECT LOC_ID, LOC_NAME
  , (@geo1.STDistance(geography::Point(ISNULL(LAT,0), 
  ISNULL(LONG,0), 4326)))/1000 as DISTANCE
from Konum
WHERE (@geo1.STDistance(geography::Point(ISNULL(LAT,0), ISNULL(LONG,0), 4326)))/1000 < 30
order by DISTANCE ASC

按别名列排序时的查询排序问题

1 个答案: